Merge pull request #9 from atupal/master

Proofreading htmlfaq.rst, index.rst, installation.rst, latexindex.rst, license.rst, python3.rst, quickstart.rst
Proofreading or reqcontext.rst
Proofreading of reqcontext.rst, shell.rst and security.rst
Merge branch 'master' of https://github.com/yinian1992/flask-docs-cn